The present invention relates to transmission and reception of a video signal.
As an interface for transmitting a video signal from a source device to a display device, a High-Definition Multimedia Interface (HDMI. A trademark of HDMI, LLC) is widely used. Further, a collaboration operation between a source device and a display device is realized based on a control communication such as Consumer Electronics Control (CEC) included in the HDMI.
In JP-A-2008-109342, the following technique is disclosed. A display device is provided with an HDMI input port. External equipment including an Nil output port can be directly connected to the HDMI input port by an HDMI cable. Further, external equipment can be connected to the display device also through relay external equipment including HDMI input and output ports. The display device includes a multiple screen display control means for performing control for simultaneously displaying each of the input images from two or more input sources on a screen and a command detection means for detecting a prescribed screen start command showing the output of the setting screen image of the external equipment transmitted by using a CEC command based on an HDMI specification from the external equipment connected to the display device. The multiple screen display control means performs control for additionally displaying the setting screen image output from the external equipment on a sub-screen when detecting the screen start command by the command detection means. In addition, an AV amplifier 2 combines videos into a two-screen mode and outputs it to a television device 1.
Also, in JP-A-2010-102053, the following technique is disclosed. It is an object of the present invention to provide a video generation device and a video display device capable of displaying the videos of two screens which make a video already displayed in a video display device, such as a broadcasting signal as a main-screen image and a video newly generated in the external part as a sub-screen video, on a one-screen with automatically and optically designed layout, without changing the structure of the inner part of a display device. Further, as a layout command of specifying each display position (coordinate value of upper left) of a main-screen video and a sub-screen video and a display size, a command of switching an input over to a terminal to which a command referred to <active source> in an HDMICEC is input is used, and further is expanded as in FIG. 3.